#include <iostream>
using namespace std;

#define MAXSIZE 50
typedef int KeyType;

typedef  struct
{
	KeyType  key;
} ElemType;

typedef  struct
{
	ElemType  *R;
	int  length;
} SSTable;

void  Create(SSTable &T)
{
	int i;
	T.R = new ElemType[MAXSIZE + 1];
	cin >> T.length;
	for (i = 1; i <= T.length; i++)
		cin >> T.R[i].key;
}

int  Search_Bin(SSTable T, KeyType k);

int main()
{
	SSTable T;  KeyType k;
	Create(T);
	cin >> k;
	int pos = Search_Bin(T, k);
	if (pos == 0) cout << "NOT FOUND" << endl;
	else cout << pos << endl;
	return 0;
}

int Search_Bin(SSTable T, KeyType k) {
	int re = 0;
	int L = 1, R = T.length, mid;
	while (L < R) {
		mid = (R - L) / 2 + L;
		if (T.R[mid].key < k) {
			L = mid + 1;
		}
		else
			R = mid;
	}
	if (T.R[L].key == k)
		re = L;

	return re;
}